<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no" />
  <title>Birds Flying</title>
  <style>
    *{      
      -webkit-touch-callout: auto; /* prevent callout to copy image, etc when tap to hold */      
      -webkit-text-size-adjust: none; /* prevent webkit from resizing text to fit */      
      -webkit-tap-highlight-color: rgba(0,0,0,0); /* make transparent link selection, adjust last value opacity 0 to 1.0 */       
      -webkit-user-select:none;
    }  
    html,body {
      width: 100%;
      height: 100%;
      padding: 0;
      margin: 0;
      max-width: 500px;
    }
    #paper {
      position: relative;
      overflow: hidden;
      width: 100%;
      padding-top: 100%;
      height: 0px;
    }
  </style>
</head>
<body>
  <div>sprites: <span id="spriteCount">1</span></div>
  <div id="paper"></div>

  <script src="https://s3.ssl.qhres.com/!ed7dc4fe/animator-0.3.2.js"></script>
  <!-- <script src="js/animator-dev.js"></script> -->
  <script src="/js/spritejs.js"></script>
  
  <script>
  (async function () {
    const container = document.getElementById('paper');
    const paper = new spritejs.Scene({container, width: 800, height: 800});

    const layer = paper.layer('fglayer', {
      handleEvent: false,
    });

    function wait(ms) {
      return new Promise((resolve) => {
        setTimeout(resolve, ms);
      });
    }

    function randomColor() {
      const r = 0 | Math.random() * 192,
        g = 0 | Math.random() * 255,
        b = 0 | Math.random() * 128;

      return `rgb(${r},${g},${b})`;
    }

    async function randomCircle(r = 25) {
      const x = 100 + Math.random() * 600,
        y = 100 + Math.random() * 600;

      const sprite = new spritejs.Sprite();
      sprite.attr({
        anchor: 0.5,
        pos: [x, y],
        size: [2 * r, 2 * r],
        borderRadius: r,
        bgcolor: randomColor(),
      });
  
      // const anim = new Animator(2000, (p) => {
      //   if(p < 0.5) {
      //     sprite.attr({scale: 0.8 + 0.6 * p})
      //   } else {
      //     sprite.attr({scale: 1.1 - 0.6 * (p - 0.5)})
      //   }
      // })

      // anim.animate().then(function f() {
      //   anim.animate().then(f)
      // })
      sprite.animate([
        {scale: 1.0},
        {scale: 0.8},
        {scale: 1.0},
        {scale: 1.1},
        {scale: 1.0},
      ], {
        duration: 3000,
        iterations: Infinity,
      });
      layer.append(sprite);
      await wait(100);
    }

    window.fglayer = layer;
    window.paper = paper;

    for(let i = 0; i < 300; i++) {
      spriteCount.innerHTML = i + 1;
      await randomCircle();
    }
  }());
  </script>
</body>
</html>